The first season of American Idol premiered on June 11, 2002 (under the full title American Idol: The Search for a Superstar) and continued until September 4, 2002. It was won by Kelly Clarkson. This season was co-hosted by Ryan Seacrest and Brian Dunkleman, the latter of whom left the show after the season ended.

The winner, Kelly Clarkson, signed with RCA Records, the label in partnership with American Idol's 19 Recordings. Immediately post-finale, Clarkson released two singles, including the coronation song, "A Moment Like This". "A Moment Like This" went on to break a thirty-eight-year-old record held by The Beatles for a song's biggest leap to number one on the Billboard Hot 100. It jumped up from number fifty-two to number one in just one week. She held that record for five years but she reclaimed that record back in 2009 with her hit single "My Life Would Suck Without You" when it jumped up from number ninety-seven to number one. Clarkson has enjoyed a successful recording career since winning, with multiple-platinum albums, a number of Top 10 hit singles and three Grammy Awards. Runner-up Justin Guarini also signed with RCA Records, eventually debuting an album in 2003 after the conclusion of season 2. RCA dropped him shortly after its debut. In addition to Clarkson and Guarini, also signed were Nikki McKibbin, Tamyra Gray, R. J. Helton, and Christina Christian.

After the finale, a special show in Las Vegas was also shown in September 23, 2002 where all 30 of the contestants who made the judges' initial cut performed during in a two-hour concert.

The show inspired a 2003 musical film, From Justin to Kelly, featuring Kelly Clarkson and Justin Guarini.

One of the more prominent auditioners this season was Tamika Bush who objected to the judges' critiques and their pronunciation of her name. She was later invited back to critique the contestants' semifinal performance. Kristin Holt who auditioned in Dallas was put through to the Hollywood rounds, but in her rush to embrace the judges, fell and slipped under the judges' table.

Kelly Clarkson was notable for being largely absent in the audition episode, and she remains the only winner whose audition was not aired in the original broadcast. The other top 10 finalists in Season 1 whose audition were not shown were Nikki McKibbin and EJ Day.

There are usually three stages in the audition process in every season, the first stage being the open call audition advertised. In this stage those auditioning each sings briefly in groups of five in front of selectors, though some may be asked to sing further. Most of those who attended are eliminated at this stage with only a limited number of auditioners selected to proceed further. In the second round they sing in front the executive producers and more are eliminated. In some later years a further round may be added before this round of audition. In the last round those who survive the first two stage sing in front of the judges and this is the audition shown on television. Those who gain at least two yeses from the three judges then receive a golden ticket to Hollywood.

In the first season, the second and third stage of the audition may take place within a single day, but in the following seasons each stage of the audition may take place on separate days. The initial audition venue need not necessarily be the final audition venue in front of the judges, and in later seasons, up to three separate venues may be used for the auditions in each city. The venues and dates of the second audition in front of the producers are not specifically listed in these pages. In the early seasons, the entire audition process in each city took place within a relatively short span of time, 3 days in the case of Season 1, but became progressively extended in later seasons until the callback date may be many weeks after the initial auditions.

The Hollywood week rounds were held in Pasadena Civic Center where 121 contestants competed for a place in the finals. The contestants first emerged on stage in groups of 9 or 10 but performed solo unaccompanied, and those who did not impress the judges were cut after the group finished their individual performances. 65 were selected to proceed on to the next round. The singers were expected to learn their songs that night and perform the next day in groups of three. The girls and boys were separated and given crash course to learn their song, which was Dionne Warwick's "I Say a Little Prayer" for the girls and "For Once in My Life" for the boys. Many however frequently forgot the lyrics. Again those who failed to impress were cut immediately after their performance. 45 made it to the next round, and the 20 cut were given their last chance to voice their opinion to the judges before leaving.

In the final round, the remaining 45 were given new songs to learn and each performed solo and a cappella. 30 contestants would be chosen after this round. In this round Justin Guarini impressed the judges and his fellow contestants alike. The Top 15 were first announced, the judges then select 15 more out of the remaining 30. The 30 were split into two groups and the judges then go to each group to announce the chosen group.

Delano Cagnolatti was initially amongst those announced as the Top 30, but he was later disqualified for falsifying his age,[7] and became the first person to be disqualified on American Idol. He was replaced by EJay Day.

The 30 contestants who reached this stage in this season were referred to in the show as the finalists.

Before their performance, the contestants took part in intensive music workshop where they were given vocal coaching by Debra Byrd and advice by stylists. The contestants were held in the Red Room before they each emerged to perform solo with piano accompaniment. There was no studio audience at this stage and the performance was pre-taped. The audience voted after each round of performance, and the results of the vote were announced the next day live. A total of 3.3 million votes were cast in the first week of voting.[8]

Below are the three semi-final groups with contestants listed in their performance order. In each group, three people advanced to the next round, based on votes by the viewers.

Following those nine singers advancing, five of the remaining 21 semi-finalists were selected by the judges to compete in the Wild Card round. Following another performance by each Wild Card contender, the judges selected one contestant to advance to the final group of 10.

EJay Day (born September 13, 1981 in Lawrenceville, Georgia, 20 years old at the time of the show) did not originally qualify for semifinal but was later chosen to replace a disqualified contestant Delano Cagnolatti.

The finals were broadcast live, in front of a live studio audience. The finals lasted for eight weeks, each finalist performed a song or songs selected from a weekly theme. During the first few weeks, contestants sang one song each. By the top four week, the contestants sang two songs each, and in the finale the two finalists performed three songs apiece.

The results of public vote were revealed in the night following the performance night in the results show. The three or two contestants in the later rounds who received the lowest number of votes were typically called the Bottom Three or Two. From the bottom three, one contestant was sent to safety so that two contestants remained and finally the contestant who received the lowest amount of votes was eliminated from the competition. A farewell video with montage of the eliminated contestant is shown.

This season largely set the pattern for later seasons, such as group performance by the contestants during the result shows, home town visits for the top 3, and performing the songs for the top 2 that would be released immediately after the finale. In this season, there are no guest mentor apart from the Burt Bacharach week where the composer helped the contestants prepare their songs.

The finale was between Kelly Clarkson and Justin Guarini, and Kelly Clarkson was declared the winner with 58% out of 15.5 million votes cast.[9] Over 110 million votes were cast over the entire season.[8]

It was revealed during the season that around 100 phone-phreak hackers with power-dialing hardware and software were able to place as many as 10,000 votes a night from a single phone line with the touch of a button.[10] However, FremantleMedia, which produces the show, contended that the hackers have had 'statistically insignificant' effect on the vote. Simon Cowell also insisted that Tamyra Gray's unexpected ouster from the show only strengthened the producers' contention that the voting was fair.[11] Nevertheless concerns were raised about possible unfairness in the situation of a tight vote.[12] Ken Warwick later said in Season 5 that equipment was put in place afterwards to address this issue but it has never detected such a problem since.[13]

Idol contestants were reported to having to sign a 'phone book-thick' contract that gives producers 'sole discretion' to pick the winners and change the rules.[14] Producer Nigel Lythgoe however said that the contracts had to anticipate every possible situation, and was not intended to rig the show in favor of any contestant.

Controversy erupted when the winner of Season 1, Kelly Clarkson, was invited to sing "The Star-Spangled Banner" in a deal arranged by her then management company, 19 Entertainment, at a special commemoration for the first anniversary of 9/11 attacks at Washington's Lincoln Memorial. Some critics suggested that Clarkson's appearance would turn a somber occasion of national mourning into a "giant promotional opportunity".[15] Kelly Clarkson herself considered withdrawing from the commemoration, saying "I think it is a bad idea ... If anybody thinks I'm trying to market anything, well, that's awful." and added "I am not going to do it."[16] She was however unable to withdraw from the event.

Semi finalist Kelli Glover appeared on the fourth season of America's Got Talent in 2009 and was eliminated during Judgement Week. She also apperared on the ninth season of America's Got Talent in 2014 and made it to the live shows.

Re-edited episodes of American Idol season 1 are now being shown in syndication as American Idol Rewind. The new episodes feature commentary from some of the first season's top 30, including runner-ups Justin Guarini, Jim Verraros, Christina Christian, Nikki McKibbin, Angela Peel, and Kelli Glover. Rewind also showcases footage that was not seen in the initial run of season 1, including Kelly Clarkson's full audition.[33]